Machine with self-sharpening means for cutting scrap materials into chips

ABSTRACT

The machine has a series of hammerlike knives which rotate about a common axis to cut scrap material fed across an anvil into small chips. In one embodiment, each knife has a massive head including a blunt front face with a V-shaped bottom cutting edge defining a pair of downwardly projecting prongs. In a second embodiment, the head of each knife has a V-shaped cutting edge defining a single downward projection. The cutting edge of both knife embodiments is straight as viewed in the cutting plane of the anvil. The bottom of the head just rearwardly of the cutting edge includes a pocket to trap and fragment by impact chips severed by the cutting edge. The cutting edges of all knives are sharpened at the same time as they rotate by a grinding cylinder which is fed either manually or automatically at a fixed rate into engagement with beveled forward faces of the knives. The grinding cylinder and its automatic feed are driven by the same means that drives the knives.

United States Patent 72] Inventor Stanley V. Ehrlich 3016 NE. 51st Ave.,Portland, Oreg. 97213 [2]] Appl. No. 881,948 [22] Filed Dec. 4, 1969[45] Patented Jan. 11, 1972 [54] MACHINE WITH SELF-SHARPENING MEANS FORCUTTING SCRAP MATERIALS INTO CHIPS 3 7 Claims, 12 Drawing Figs. [52] US.Cl 241/101 M, 241/101 R, 241/194, 51/247 [51] Int. Cl B02c 23/00, B02c13/28, 1324b 3/00 [50] FieldofSearch 241/101, 194;5'1/246, 247, 248,165.82;56/250; 172/437; 7 76/85 [56] References Cited UNITED STATESPATENTS 2,738,629 3/1956 Schreiber 51/249 2,819,746 1/1958 Baglioni5I/247X 2,829,692 4/1958 Innocent i I 51 /247 X that drives the knives.

2,835,299 5/1958 Pollmann 5l/247X Primary ExaminerTheron E. CondonAssistant ExaminerR. C. Riordon Attorney-Buckhorn, Blore, Klarquist andSparkman ABSTRACT: The machine has a series of hammerlike knives whichrotate about a common axis to cut scrap material fed across an anvilinto small chips. In one embodiment, each knife has a massive headincluding a blunt front face with a V- shaped bottom cutting edgedefining a pair of downwardly projecting prongs. In a second embodiment,the head of each knife has a V-shaped cutting edge defining a singledownward projection. The cutting edge of both knife embodiments isstraight as viewed in the cutting plane of the anvil. The bottom of thehead just rearwardly of the cutting edge includes a pocket to.trap andfragment by impact chips severed by the cutting edge. The cutting edgesof all knives are sharpened at the same time as they rotate by agrinding cylinder which is fed either manually or automatically at afixed rate into engagement with beveled forward faces of the knives. Thegrinding cylinder and its automatic feed are driven by the same meansPATENTEU mu 1 i972 SHEET 1 [1F 4 STANLEY v. EHRLICH BUG/(HORN, BLORE,KLAROU/ST 8 SPAR/(MAN A T 7' ORA/E Y5 PATENTED JAN] 1 1972 SHEET 3 OF 4FIG. 4

FIG. 5

STANLEY V. EHRLI CH I/VVEWTOR :FD:: :H

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PATENTED mu 1 I972 SHEET '4 BF 4 FIG. l2

STANLEY V. EHRLICH INVENTOR BUCKHORN, BtORE, KLARQUIST & SPARKMANATTORNEYS MACHINE WITH SELF-SHARPENING MEANS FOR CUTTING SCRAP MATERIALSINTO CHIPS BACKGROUND OF THE INVENTION Filed of the Invention Thepresent invention relates to apparatus for reducing bulk scrap materialssuch as railroad ties, scrap lumber, conduit, masonry and othermaterials commonly found in old buildings into small chips to increasethe ease of disposing of such material.

2. Description of the Prior ARt The only machine known that is capableof reducing by cutting scrap materials such as metals, masonry, agedlumber and other relatively hard and incompressible materials com monlyfound in old buildings being wrecked is described in my copending patentapplication, Ser. No. 71 1,658, filed Mar. 8, 1968, now U.S. Pat. No.3,580,517 and entitled Apparatus for Chipping Scrap Materials. Themachine of the aforementioned application has been highly successful forits intended purpose. However, the hammerlike knives of such machinecannot readily be sharpened without shutting down the machine forsubstantial periods of time and painstakingly grinding each of themultitude of hammer knives individually, which, of course, is a long andtedious process.

Thus there is a need for a machine of this general type having cuttingelements which can be readily self-sharpened by apparatus built into themachine, with a minimum. of time loss and effort.

SUMMARY OF THE INVENTION The present invention fulfills the foregoingneed by providing a machine which fulfills the same general purpose. asmy prior machine, but with specially designed hammerlike knives whichcan be sharpened as they rotate through the use of a built-in rotatinggrinding wheel. Automatic means feed the wheel into grinding engagementwith outer cutting surfaces of the knives at a predetermined rate toremove the desired amount of metal. lnfeed and withdrawal of the wheelcan also be accomplished manuallyj Means are also provided for adjustingthe positioning of the cutting edges of the knives with respect to ananvil to compensate for the metal removed from the knives during thesharpening operation. A stone facing device for dressing the grindingwheel is also build into the machine.

The self-sharpening arrangement as described enables the cuttingelements to be serviced while the machine remains at the job site andwithout losing any production time, The knives may be sharpened, forexample, in a very short period of time following a days work.Furthermore, with the device as described, the knives may be sharpenedmore frequently than would otherwise be the case whereby the knives arekept in top condition for cutting.

A specific feature of the invention is a hammer knife with a bluntforward face which defines a continuous straight cutting edge in thecutting plane of the knives, but which is V-shaped as viewed toward thefront of the knife to define one or two downwardly projecting prongs forpenetrating hard scrap materials.

Another feature is a pocket in the bottom of each knife just rearwardlyof the cutting edge which receives chips of material severed by theknife and tends to explode these chips into even smaller fragments.

Further aspects of the invention are automatic feed and drive means forthe sharpening mechanism which are driven by the power source thatdrives the knives.

In another aspect of the invention, the amount of metal removed from theknives during each sharpening operation can be accurately determined andcontrolled.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and other objects andadvantages of the present invention will become more apparent from thefollowing detailed description which proceeds with reference to theaccompanying drawings wherein:

FIG. 1 is a side elevational view of an overall machine in accordancewith the invention;

FIG. 2 is an elevational view taken along the line 2-2 of FIG. 1;

FIG. 3 is an elevational view of the same portion of the machine asshown in FIG. 2 and taken along the line 3-3 of FIG. 2, with portionsbroken away for clarity;

FIG. 4 is a horizontal sectional view taken along the line 4 4 of FIG.3;

FIG. 5 is an enlarged view of the automatic grinding wheel feed portionof FIG. 2 with supporting elements removed for clarity;

FIG. 6 is a view on an enlarged scale taken along the line 6-6 of FIG.2;

FIG. 7 is a perspective view looking at the forward and lower surfacesof a hammer-knife in accordance with the invention;

FIG. 8 is a side view of the hammer knife of FIG. 5;

FIG. 9 is a front view of the hammer knife of FIG. 5;

FIG. 10 is a perspective view looking toward the bottom and one side ofa modified hammer knife of the invention;

FIG. 11 is a side view of the hammer knife of FIG. 10; and

FIG. 12 is a front view of the hammer knife of FIG. 10.

DETAILED DESCRIPTION General Arrangement With reference to the drawings,a machine for chipping scrap materials of the invention is showngenerally at 10 in FIG. 1. This machine includes a supporting trailervehicle 12 having a frame portion 14 with a flat bed 16. The frame issupported on rear wheels 18 and telescoping front leg 20. Telescopingauxiliary rear legs 21 can be lowered into engagement with the groundfor stabilizing the trailer during operation of the chipping apparatus.A hydraulic reservoir 22 is mounted at the forward end of bed 16. Aninternal combustion engine 24 mounted on the bed just rearwardly of thehydraulic reservoir drives the chipping apparatus 16 through a beltdrive 28.

A belt conveyor 30 suspended from the underside of the trailer frame 14extends laterally beneath the chipping apparatus 26. This conveyorreceives chipping material discharged through a bottom opening of thechipping apparatus and conveys it to an awaiting carrier or pilealongside the trailer.

The portion of the trailer bed rearwardly of chipping apparatus 26 isoccupied by a scrap-receiving bin 32 is mounted at a downwardinclination from an open rear end 34 toward chipping apparatus 26.Support arms 36 support the front of the bin and are pivoted at theirupper ends to support frames 37 to permit fore-and-aft oscillation ofthe bin. A protective screen 38 keeps material within the bin fromriding up over its front end into the region of the chipping apparatusand engine.

The rear end of the bin is supported on coil springs 40. The rear end isalso connected to an eccentric vibration device 42 driven by a hydraulicmotor 43 through belt drive 44 to provide the rear portion of the binwith a rotary vibratory motion. This device is explained more fully inmy aforesaid prior application, Ser. No. 71 1,658. Because of themounting of the front of the bin in a way that does not permit verticalmovement, the rotary motion at the rear of the bin is translated toforwardand-rearward oscillating motion which gradually feeds materialinto chipper unit 26 through a front end opening of the bin.

As a further aid to feeding materials from the bin toward chipping unit26, a series of laterally spaced-apart endless drag chains 46 have upperflights which extend along the inside bottom of the bin throughoutsubstantially its entire length. If desired, the chain may be providedwith outwardly projecting lugs 48 which tend to grab the scrap materialand thus aid in the dragging action of the chain.

A suitable rotatable ranking drum with radially extending tines (notshown) may be mounted within the front end of the bin near the entranceto the chipper unit if desired for aiding and controlling the rate offeeding of material into the infeed opening of the chipper unit 26. Sucha rotary raking element is shown, for example, in FIGS. 1 and 2 of myaforementioned application, Ser. No. 711,658. When such a raking elementis used, it has been found desirable to provide means for rotating theelement in both directions so that the material being fed toward thechipping unit can be reversed if desired in the event of a Jam-up at theentrance to such unit.

Although the apparatus has been shown and described as mounted on ahighway trailer vehicle, it is to be understood that the same basiccomponents could be mounted on a railway flat car, as, for example, whenthe machine is to be used in disintegrating old railroad ties.Similarly, any other suitable vehicle may be used as a mounting meansfor the components of the apparatus. It may also be desirable in someinstances to slope the receiving bin upwardly toward the chipping unit,as, for example, when loading materials from ground level. In suchinstances, it may be preferably to omit the vibrator.

Chipping Unit For an understanding of the interior details of thescrapchipping unit 26 of the apparatus, reference is made to FIGS. 2through 6, and to FIGS. 3, 4, and 5 of my aforementioned application,Ser. No. 711,658. The chipping unit of the present invention is similarin general arrangement to the chipping unit of my prior application withrespect to the rotor construction and the pivotal mounting of the seriesof laterally adjacent hammerlike knife members between spaced platesfixed to the rotor shaft. Reference is made to my prior application foran understanding of such rotor and mounting details.

As shown in FIGS. 2 and 3, chipping unit 26 includes a generallysemicylindrical housing 50 having a curved cover plate 52 pivoted at 53to a pair of supporting arms 54 which are adapted to swing about theirconnections 55 to opposite end walls of the housing to place the coverover a rear access opening 56 providedfor servicing and inspection. Thelower portion of the housing is rigidly mounted on I-beam base framemembers 57 which in turn are fixed to the bed of the trailer.

A rotor means 58 mounting a series of hammer like knife members 60 ispositioned within the housing and includes a large main driven shaft 62which extends centrally through the interior of the housing and throughits opposite end walls. Main shaft 62 is journaled near its oppositeends in bearing members 64, 65. Anextension 62a of shaft 62 mounts alarge pulley wheel 66 which transmits power from the engine 24 throughbelt 28 of FIG. 1. Shaft-bearing members 64, 65 include flange portions68 fastened to shim plates 70, 72 and to an upper portion of base framemember 57. Plates 70 are readily removable for adjusting the verticallevel of the rotor with respect to the base frame 56, in order to adjustthe cooperative cutting relationship between the knife members 60 and ananvil 74. The anvil is mounted on the base frame at an infeed opening 76of the chipping housing.

Setscrew adjusting means 77, 78 on plates 70 enable horizontaladjustment of rotor 58 with respect to anvil 74 to compensate for metalremoved from the hammer knives through the sharpening action removedfrom the hammer knives through the sharpening action of sharpeningapparatus to be described.

As shown best in FIG. 2, rotor 58 includes a series, in this instance20, large-diameter discs 80 fixed to shaft 62 within housing 50 inlaterally spaced-apart pairs. One disc of each pair abuts another discof the next adjacent pair. Spacer sleeve members (not shown, but shownin the aforementioned prior application) are positioned on shaft 62between the spaced discs to maintain the desired spacing.

Several, in this case three, hammer knives 60 are mounted on pivot pins82 between each spaced pair of discs 80 near the outer periphery of suchdiscs. Although the hammer knives between only one pair of discs isshown in FIGS. 2 and 3, it is to be understood that there are an equalnumber of hammer knives between each of the other four pairs of discs.Furthermore, the hammer knives between each pair of discs are notaligned laterally with the hammer knives between the adjacent pairs ofdiscs so as to minimize stress imposed on the rotor elements at anygiven time and to minimize vibration. The offset or staggeredrelationship between laterally related hammer knives is illustrated inthe aforementioned pending application, Ser. No. 711,658.

From the foregoing it will be apparent that there are a total of 15hammer knives with three being equally circumferentially spaced abouteach pair of discs so that a total of 15 hammer knives act on materialfed across the anvil during each revolution of the rotor shaft 62. Yetthe hammer knives on laterally adjacent pairs of discs are staggered insuch a manner that only one or two hammer knives act on the material atany given instant.

Anvil 74 includes a removable and rectangular upper plate 84 made ofspecially hardened material for long wear. Anvil plate 84' defines fourlaterally upstanding, straight cutting edges 86, only one of which isoperative at any given time. Plate 84 is symmetrical about longitudinaland lateral axes so that when one of the cutting edges 86 is worn, theplate may be reversed top-to-bottom and side-to-side so that eventuallyall four cutting edges 86 can be utilized.

The hammer knives are mounted for pivotal movement about axes parallelto the axis of the rotor to enable each knife to pivot rearwardly awayfrom the anvil cutting edge and provide considerable clearance betweenthe knife member and the anvil. This safety feature protects themachinery from damage should a knife strike an exceptionally hard objectwhich is unable to penetrate as the rotor turns in a clockwise directiondownwardly toward the anvil as shown in FIG. 3. Each of the hammerknives is provided with laterally extending shoulder portions 92 whichextend in overlapping relationship to the outer peripheries of discs 80.These shoulders limit the amount of rearward pivoting movement of theknives, and thereby minimize the possibility of generating extraneousstresses and vibrations.

Frame members 57 also define a central discharge opening within housing50 through which chipped scrap material cut by the hammer knives 60passes in a downward direction toward discharge conveyor 30 beneath thetrailer frame. Of course, bed 16 of the trailer itself must also beprovided with a corresponding vertically aligned opening (not shown) toprovide an unobstructed vertical passageway downwardly from within therotor housing to the discharge conveyor.

Sharpening Apparatus As shown in FIG. 3, housing 50 includes rearwardside extensions 93 between which a grinding cylinder 94 extendslaterally through a length coextensive with the length of rotor 58. Thegrinding cylinder is composed of a series of cylindrical grinding wheelsegments 96 as shown in FIG. 2 fixed to a laterally extending shaft 98suitable journaled at its opposite ends in bearing members 100, one ofwhich is shown in FIGS. 3 and 6. Referring to FIG. 6, each bearingmember 100 forms part of a slide member 102 mounted for in-and-outsliding movement along horizontal guide bars 103, 104 defining ahorizontal slot 101 housing extension 93. The bearing member 100 for theopposite end of shaft 98 is identical to the one shown and described andsimilarly forms part of another slide member (not shown) mounted in asimilar manner in the opposite sidewall extension of the housing.

Both manual and automatic means are provided for moving grinding wheel94 toward and away from the rotating knife members 60 through slidingmovement of slides 102. Referring to FIGS. 2, 3 and 6, these meansinclude a pair of screwthreaded shafts 105, one of which is threadedinto a nut portion 106 of each slide member 102. The outer ends ofshafts carry sprockets 107, 108. As shown in FIG. 6, shaft 105 isrotatably mounted in a bearing member 109 on a supporting bar 1 10 whichprevents axial movement of the shaft, thus rotation of shaft 105 causessliding movement of slide 102 and its supported grinding wheel 94.

Support bar 110 carries a second sprocket 111 below sprocket 107. Thethree sprockets 107, 108 and 111 are interconnected by an endless chain112. Sprocket 111 mounts a crank handle 113 to facilitate rotation ofsuch sprocket manually. Rotation of sprocket 111 induces simultaneousrotation of sprockets 107, 108 and their connected screw shafts 105through chain 112, thereby sliding slides 102 and their supportedgrinding wheel 94 horizontally in or out as desired.

The automatic means for feeding grinding wheel 94 toward the hammerknives includes the sprockets 107, 108, chain 112, screw shafts 105 androtor shaft 62 already mentioned, and a drive train for transmittingpower from rotor shaft 62 to sprocket 107. Such drive train includes apulley wheel 114 on shaft 62 transmitting power through a belt 115 to asmaller pulley 116 mounted on one end of a shaft 117. Shaft 117 includesa portion 118 of reduced diameter which receives a belt 119 fortransmitting power to a pulley 120. Pulley 120 is mounted on the inputshaft 121 of a speed-reducing gear box 122 having a large-diameteroutput shaft 123.

As shown in FIG. 5, shaft 123 has an eccentric portion 124 whichpivotally mounts a pawl 125. Pawl 125 can be swung to a position shownwherein its outer end engages a ratchettoothed section 126 of sprocket107 also having the usual chain-engaging sprocket teeth 127. Thus whenshaft 123 is driven at slow speed in a counterclockwise direction asviewed in FIG. 5 pawl 125 advances one ratchet tooth of sprocket 107during each revolution of shaft 123. When considering the additionalreduction provided by screw shafts 105, rotation of sprocket 107 in acounterclockwise direction through a distance of one ratchet toothadvances the grinding wheel through a very small predetermined'distance.This feature makes it exceptionally easy to determine the amount ofmetal removed from the hammer knives by counting the number of ratchetteeth advanced by the pawl. To disengage the automatic feed, the pawl issimply swung out of engagement with the ratchet teeth 126 of sprocket107.

Power for rotating grinding wheel 94 is also taken from rotor shaft 62through the previously mentioned pulley 114, belt 115, pulley 116 andshaft 117. Shaft 117 carries a second pulley 128 as shown in FIG. 2which transmits power through a belt 129 to a pulley 130 on the end ofgrinding wheel drive shaft 98.

To compensate for the variable positioning of shaft 98 as it moves inand out within slot 101, shaft 1 17 is journaled within bearing memberson a platform 131 which is spring-biased against the tension of belt129. Thus as grinding wheel shaft 94 moves in a direction tending toshorten the distance between pulley wheels 128 and 130, platform 131pivots away from shaft 98, keeping belt 129 taut. Platform 131 ispivoted at 132 to base frame 57. The spring-biasing means for theplatform includes a rod 133 anchored to a center portion of the platformand extending downwardly through a plate 134 fixed to frame 57. A coilspring 135 is compressed between plate 134 and an enlarged seat 136 nearthe lower end of rod 133, thereby tending to pivot platform 131downwardly about its pivot connection 312 to the frame.

As platform 131 pivots up and down, there is a tendency to slacken andtighten drive belt 115 from the rotor shaft. To counter this tendency,an idler pulley 137 is mounted on an arm 138 which is spring-biasedupwardly on a frame plate 139. Idler pulley 137 engages a lower portionof belt 1 and maintains constant upward pressure on such belt, therebykeeping belt 115 taut regardless of the position of platform 131.

Belt 119 also has a tendency to slacken and tighten as platform 131pivots up and down. However, only a very light friction is required torotate pulley 120. Therefore, belt 119 is made of a highly elasticmaterial which maintains sufficient frictional engagement with pulley120 to drive such pulley despite the variable positioning of platform131.

Referring to FIGS. 2, 3 and 6, means are also provided for dressinggrinding wheel 94 to keep it in good sharpening condition. Such meansincludes a slide bar 140 mounted at its opposite ends in brackets 141 onhousing sidewall extensions 93. A tool holder 142 is mounted for slidingmovement on slide bar 140. The tool holder supports a set of dressingtools 143. The surface of grinding wheel 94 can be retracted intoengagement with the dressing tools by operation of crank 113.

Hammer knife Details The hammer knives 60 are of a special design whichenables them to be self-sharpened using grinding wheel 94. The designalso makes the knives particularly effective in disintegrating chipssevered by their cutting edges.

All of the hammer knives are identical in size and shape. Referring toFIGS. 7, 8 and 9, each includes a rear body portion 145 and an enlargedmassive head portion 146 which extends laterally from the body portionand joins the body portion along the previously mentioned shoulders 92.Body portion 136 includes a through opening 147 extending from side toside of the knife member and of large enough diameter to receive pivotpin 82 and associated bushing member (not shown).

Head portion 146 includes a blunt flat frontal surface 148 which meets alower forward cutting surface 149. Forward cutting surface 149 meets apair of laterally inwardly and upwardly sloping bottom cutting surfaces150, 151 at a lower front edge 152 defining the cutting edge of thehammer knife.

Sloping bottom surfaces 150, 151 also define a pocket 153 into whichchips severed by cutting edge 152 are driven. The sloping nature ofbottom surfaces 150, 151 also causes these surfaces together withforward cutting face 149 to define a pair of sharp projections 154, 155as clearly shown in FIG. 9 at the lateral extremities of cutting edge152. These projections increase the penetrating effect of the cuttingedge as it strikes a piece of scrap material.

As viewed in a direction toward the front of the knife, cutting edge 152is V-shaped sloping in a direction inwardly and upwardly toward thelongitudinal median plane of the knife. However, as viewed in thecutting plane, or a plane 157 extending normal to the plane in which theforward cutting face 149 lies, cutting edge 152, or a projection of suchedge, will define a straight line. The cutting plane 157 is alsorepresented by the plane in which the top surface of anvil plate 84 andanvil cutting edge 86 lie. Thus, unlike the sawtooth-type cutting edgeprovided on the anvil of the aforesaid prior application, Ser. No.711,658, anvil cutting edge 86 is straight and therefore easier tomanufacture and maintain than the former.

Upper front face 148 of the knife head extends at a rearward inclinationwith respect to the plane of lower forward cutting face 149 to provideclearance for the hammer knife as it proceeds downwardly past the anvilcutting edge. As viewed in FIG. 9, forward cutting face 149 extends at aforward inclination from cutting edge 152. On the other hand, frontclearance face 148 extends at a rear ward inclination from itsintersection with forward cutting face 149.

The beveled forward cutting face 149 in the face which is ground bygrinding wheel 94 to maintain cutting edge 152 in a sharpened condition.Although grinding wheel 94, because of its cylindrical surface, willhave a tendency to hollow-grind face 149, such tendency will becounteracted by the opposite curved path of travel of such face as it isground. Thus beveled face 149 will be maintained in a very nearly flatcondition as it recedes rearwardly through successive grindingoperations. Each knife member will have a long life despite the factthat cutting face 149 and cutting edge 152 will gradually recede throughsubsequent grinding operations because of the great depth of the head asmeasured rearwardly from the forward cutting face.

Modified Hammer Knife Referring to FIGS. 10, 11 and 12, a modifiedhammer knife 160 has a relatively thin main body portion 162- and anenlarged head portion 164 with a shoulder 166 separating the head fromthe body. Hammer knife 160 includes a rear opening 168 for receiving thepivot shaft of the rotor on which the hammer knife is adapted to bemounted.

Hammer knife 160 includes an upper front face portion 170 which meets alower, rearwardly inclined front cutting face portion 172. Lower frontface 172 meets a pair of side surfaces 173, 174 which angle inwardly anddownwardly from opposite sidewalls 175, 176 of the head to define agenerally V-shaped cutting edge 178 terminating at a single point 179.

The intersection of surfaces 173 and 174 extends rearwardly from thepoint 179 to define a bottom edge 180 of a single prong 182 formed bythe surfaces just described. Prong 182 extends below an adjacent bottomsurface 186 of the head to define a pocket 188 in the region just behindthe prong. Chunks of material severed by the hammer knife are driveninto this pocket and thus disintegrated into smaller particles. In thisrespect the hammer knife has an action similar to the two-prongedversion of the hammer knife shown in F IG. 5.

Like the previously described double-pronged hammer knife, hammer knife160 has the ability to be self-sharpened using the apparatus that isshown in FIG. 3. In this regard cutting face 172 is periodicallyreground to maintain the forward cutting edges 178 in a sharpenedcondition.

Operation During normal operation of the apparatus to disintegrate scrapmaterial, the rotor as viewed in FIG. 3 is rotated in a clockwisedirection as bin 32 is vibrated and drag chains 46 rotate to feedmaterial at a desired rate into the chipper housing and across theanvil. For example, the rate of feed of material onto the anvil can beadjusted so that the knife members take a one-quarter to one-third inchbite with each impact-shear stroke, which is normal operating speedswould destroy scrap material at a rate of 36 running feet per minute.

As each hammer knife passes in shearing relationship to the cutting edgeof the anvil, the two points 154, 155 of each knife cutting edge readilypenetrate scrap material to sever chips and drive these chips intopocket 153. The pocket first tends to compress the chips and finallyexplodes them into even smaller fragments as a result of the high impactforces generated. The downwardly rotating knives also drive theresulting scrap fragment downwardly through the bottom discharge openingof the chipper housing and onto discharge conveyor 30. This conveyorthen transfers the material to one side of the machine, and, if desired,to an elevating conveyor (not shown) which dumps the scrap chips into awaiting truck or other carrier.

At the end of a days work, the condition of the cutting edges of thehammer knifes is inspected simply by raising access cover 52. Ifsharpening is indicated, the operator first determines how much metalshould be removed to resharpen the cutting edges of the knives. Then herotates crank 113 in a direction to advance grinding wheel 94 into thehousing until its grinding surface is positioned adjacent the forwardcutting faces 149 of the knife members. Thereafter the operator startsup engine 24 to drive the rotor and attached knives. He also engages theautomatic feed by swinging pawl 125 into contact with ratchet teeth 126of sprocket 107. Thus power is transmitted by rotor shaft 62 throughbelt and pulley drive train described in rotate grinding wheel 94clockwise and simultaneously advance the wheel into engagement with theforward cutting faces of the rotating knives at a predetermined rate.This rate is based on the known speed ratio between rotor shaft 62 andoutput shaft 123 of gear reducer 122. For example, in one embodiment,0.003 of an inch of metal is removed from each knife for every 6,000revolutions of the rotor shaft. A counter can be mounted on a controlpanel if desired to keep track of the number of shaft revolutions andthus accurately control the amount of metal removed during eachsharpening operation. Alternatively the amount of metal removed can bedetermined in terms of the number of ratchet teeth advanced on sprocket107. The operator can readily keep track of ratchet tooth movementusually and shut down the machine when the required number of teeth havebeen advanced by the pawl.

Following the grinding operation, grinding wheel 94 is withdrawn bydisengaging pawl from sprocket 107 and manually cranking sprocket 111 inthe required direction. Thereafter it might be necessary to repositionthe rotor with respect to the anvil, depending on how much material hasbeen removed from the hammer knives. For example, if the total ofone-sixteenth of an inch is removed from the forward cutting face ofeach knife, it is necessary to shift the axis of rotor shaft 62 towardthe anvil a corresponding distance by adjustment of setscrews 77, 78.

Having illustrated the principles of my inventions in what are presentlypreferred embodiments, it should be apparent that such embodimentspermit of modification in arrangement and detail. It is my intention notto be limited by the specific embodiments disclosed, but to includewithin the scope of my invention all such modifications and equivalentconstructions.

I claim:

1. In an apparatus for cutting scrap materials into small chips:

anvil means defining a stationary cutting edge,

means for feeding scrap material across said anvil means and over saidcutting edge,

rotor means pivotally mounting a plurality of laterally relatedhammerlike knife members for pivoting movement about pivot axes parallelto and SPACED equal distances from a common rotor axis extending in thegeneral direction of said anvil cutting edge in a manner so that eachsaid knife member rotates into periodic cutting relationship with saidanvil cutting edge,

each of said knife members including a knife cutting edge defined by aforward cutting face and a bottom cutting face thereof,

and sharpening means movable into engagement with said forward cuttingfaces of said knife members as said knife members rotate to sharpen saidknife cutting edges, said sharpening means including a cylindricalgrinding wheel having a length substantially coextensive with thelateral extent of said plurality of knife members, and rotatable in thesame direction as said knife members,

self-feeding means for feeding said grinding wheel toward said knifemembers at a predetermined slow rate of travel, and manually operatedoverride means for moving said grinding wheel toward and away from saidknife members at a fast rate of travel.

2. Apparatus according to claim 1 wherein said self-feeding means andsaid manual override means include screw means operable upon rotation tomove said grinding wheel toward and away from said knife members, andsaid self-feeding means further including drive means for rotating saidscrew means drivingly connected to means for rotating said knifemembers, said drive means including speed-reducing means, and eccentricmeans driving a pawl and ratchet means whereby said screw means isrotated at a predetermined slower speed than said knife members and theamount of metal removed from said knife members can be determined bycounting strokes of said ratchet and pawl means, and clutch means forselectively disengaging said drive means.

3. Apparatus according to claim 2 wherein said means for rotating saidgrinding wheel means includes second drive means drivingly connected tosaid means for rotating said knife members, said second drive meansincluding automatic adjustment means operable to compensate for thevarying distance between the rotational axis of said wheel means and therotational axis of said knife members to provide a continuous drivetherebetween.

4. Apparatus according to claim 2 wherein said manual override meansincludes means for manually rotating said screw means with said clutchmeans disengaged.

5. Apparatus according to claim 1 wherein said knife cutting edge isV-shaped as viewed toward the front of said knife member so as to definea pair of pointed projections at the laterally opposite extremities ofsaid knife cutting edge.

6. Apparatus according to claim 5 wherein each knife member includes abottom surface intersecting said forward cutting face to define saidknife cutting edge, said bottom surl0 face being recessed rearwardly ofsaid knife cutting edge and recessed laterally inwardly of oppositelower side edges of said UNHED SlA'ljLfi kA'i'bNl' Ulllbb CERTIFICATE OFCORRECTIGN Patent No. 3,633,833 Dated January 11, 1972 lnventor(s)STANLEY ICH It is certified that error appears in the above-identifiedpatent and that said Letters Patent are hereby corrected as shown below:Column 1, line 5, "Filed" should be -Fi-eld--; Column 1, line 1 "ARt"should be --Art; Column 1, line 44, "build" should be --built-*; Column2 line 39 "16" should be -26; Column 2, line 43, "chipping" should be-chipped--; Column 2, line 48, after "bin 32" the following has beenomitted: Bin 32--; Column 2 line 56; "vibration" should be --vibrator-;Column 2 line 73, "ranking" should be --raking-- Column 3, line 8"Jam-up" should be --jam-up-; Column .3, line 19 "preferably" should bereferable"; Colurrm 3', line 57, "chipping" should be chipper-; Column3, lines' 61-62, the phrase "removedjfron the hammer knives through thesharpening action" has been dupli cated; Column 3, line 65, "20" shouldbe ten--; Column 4, line 57, "suitable" should be --suitably--; Column 5line 46,

"the" should be -an--; Column 5, line 62 "312" should be --'-l32---;Column 6, line 60, "rear ward" should be -rearwa-rd--; Column 6, line 62"in" should be --is--; Column 6, line 67, "opposite" should be--opposite-ly; Column 7, line 39], "is" should be --at-- Column 7,- line48 "fragment" should be --fragments, Column 7, line 67, "in" should beto--; Columnv 8, line 5, "usually" should be ---visually; Column 8 line33, claim 1, ,"SPACED" should be --spaced; Column 9 line 6, claim 5,after "pointed" the word --downward was omitted; Column 10 line 8, claim7-, after "forming" the word -thewas omitted.-

Signed and sealed this 22nd day oi August 1972'.

. Att'est:

EDWARD MYFLFITGHHRHTR. ROBERT GoW-scH/im Attesting Oificer' Commissionerof Pateni

1. In an apparatus for cutting scrap materials into small chips: anvilmeans defining a stationary cutting edge, means for feeding scrapmaterial across said anvil means and over said cutting edge, rotor meanspivotally mounting a plurality of laterally related hammerlike knifemembers for pivoting movement about pivot axes parallel to and SPACEDequal distances from a common rotor axis extending in the generaldirection of said anvil cutting edge in a manner so that each said knifemember rotates into periodic cutting relationship with said anvilcutting edge, each of said knife members including a knife cutting edgedefined by a forward cutting face and a bottom cutting face thereof, andsharpening means movable into engagement with said forward cutting facesof said knife members as said knife members rotate to sharpen said knifecutting edges, said sharpEning means including a cylindrical grindingwheel having a length substantially coextensive with the lateral extentof said plurality of knife members, and rotatable in the same directionas said knife members, self-feeding means for feeding said grindingwheel toward said knife members at a predetermined slow rate of travel,and manually operated override means for moving said grinding wheeltoward and away from said knife members at a fast rate of travel. 2.Apparatus according to claim 1 wherein said self-feeding means and saidmanual override means include screw means operable upon rotation to movesaid grinding wheel toward and away from said knife members, and saidself-feeding means further including drive means for rotating said screwmeans drivingly connected to means for rotating said knife members, saiddrive means including speed-reducing means, and eccentric means drivinga pawl and ratchet means whereby said screw means is rotated at apredetermined slower speed than said knife members and the amount ofmetal removed from said knife members can be determined by countingstrokes of said ratchet and pawl means, and clutch means for selectivelydisengaging said drive means.
 3. Apparatus according to claim 2 whereinsaid means for rotating said grinding wheel means includes second drivemeans drivingly connected to said means for rotating said knife members,said second drive means including automatic adjustment means operable tocompensate for the varying distance between the rotational axis of saidwheel means and the rotational axis of said knife members to provide acontinuous drive therebetween.
 4. Apparatus according to claim 2 whereinsaid manual override means includes means for manually rotating saidscrew means with said clutch means disengaged.
 5. Apparatus according toclaim 1 wherein said knife cutting edge is V-shaped as viewed toward thefront of said knife member so as to define a pair of pointed projectionsat the laterally opposite extremities of said knife cutting edge. 6.Apparatus according to claim 5 wherein each knife member includes abottom surface intersecting said forward cutting face to define saidknife cutting edge, said bottom surface being recessed rearwardly ofsaid knife cutting edge and recessed laterally inwardly of oppositelower side edges of said knife member to define a pocket for receivingmaterial severed by said knife cutting edge.
 7. Apparatus according toclaim 1 wherein each said knife member includes a bottom surface portionintersecting said forward cutting face at a V-shaped knife cutting edge,said V-shaped knife cutting edge forming a downward pointed projectionfor penetrating, crushing and severing material and forming forward endof a pocket defined by said bottom surface portion for trapping andfragmenting by impact material severed by said projection.